This invention relates to a method and compositions for conditioning phonograph records by application of a very thin film of certain quaternary ammonium compounds. In addition to cleaning and destaticizing the record, remarkable and measurable improvements in audio playback quality are achieved with some of these compounds.
The cleaning of phonograph record surfaces is a well-recognized and longstanding problem. While it is essential to remove dirt and other contaminants from very small grooves on the surface, even a slight scratching of the grooves can affect the reproduction quality. Known methods for cleaning a record surface include simple mechanical removal of dust with a brush or air jet stream, although these methods are generally not particularly effective if the dust is adhesive to the surface, whether by its own physical characteristics or with an electrostatic charge, or for inherently sticky substances, such as fingerprints. Rubbing of the surface with cleaners which may have abrasive contaminants is also dangerous to the integrity of the grooves. A somewhat more elaborate type of brush-operated cleaner is shown in Taylor, U.S. Pat. No. 3,150,401, wherein a record is rotated through a series of brushes, and strips of polonium impregnated material are located in the vicinity of the record to drain off static electricity.
Other types of record cleaners consist of hand-operated rollers, commonly wrapped with an adhesive material facing outward, such that as the roller traverses the record surface, dust deposited on the surface is picked up and retained by the roller. A device of this type is disclosed in U.S. Pat. No. 3,958,292. Another roller type cleaner is disclosed in Kawabe, U.S. Pat. No. 4,128,909.
While several of the known surface cleaning treatments are adequate to remove dust from the record surface, none of the known treatments has any appreciable effect on the actual sound reproduction qualities of the record. It has been found in accordance with the present invention that application of a very thin film of certain quaternary ammonium compounds to the record surface not only cleans the record and leaves it static free, but improves stylus life, and in some cases, remarkably enhances the aural qualities of the record. The quaternary ammonium compounds useful in the treatment of the invention are commonly used as fabric softeners, and generally have at least one hydrocarbon radical containing from 12 to 22 carbon atoms. The compounds imparting significantly improved aural qualities have at least one hydrocarbon radical having 14-18 carbon atoms, preferably derived from tallow.
Quaternary ammonium compounds are known antistatic components and have generically been disclosed as useful antistatic ingredients for phonograph record cleaners. For example, Pardee, U.S. Pat. No. 4,096,079 discloses "fatty quaternary ammonium compounds" to be useful antistatic agents. Similarly, Japanese patent 30514 discloses the use of trimethyl dodecylammonium chloride as an antistatic agent in an aqueous silicone-oil containing record cleaner. When used as antistatic agents, these compounds are present in extremely small amounts, e.g., about 0.01%w. Other disclosures of antistatic utility of these compounds is found in Friedman et al., U.S. Pat. No. 4,152,288, Dasher et al., U.S. Pat. No. 4,129,505, and Roche, Fr. No. 2,451,960.
Accordingly, it is an object of the present invention to provide a composition for application to a phonograph record surface which improves the aural qualities of the record in addition to cleaning and destaticizing the surface. It is a further object of the invention to provide a thin, long-lasting coating for a phonograph record that will subsist for a substantial number of plays before recoating is necessary. It is yet a further object of the invention to provide a method of application of a thin film of quaternary ammonium compound which permits the material to be applied with a very thin, even coating, to the record, without leaving any undue accumulations of material on the record.